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bioRxiv · 10.1101/2022.04.18.488685

A chip-based array for high-resolution fluorescence characterization of free-standing horizontal lipid membranes under voltage clamp

Ensslen, T.·Behrends, J. C.
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Abstract

Optical techniques, such as fluorescence microscopy, are of great value in characterizing the structural dynamics of membranes and membrane proteins. A particular challenge is to combine high-resolution optical measurements with high-resolution voltage clamp electrical recordings providing direct information on e.g. single ion channel gating and/or membrane capacitance. Here, we report on a novel chip-based array device which facilitates optical access with water or oil-immersion objectives of high numerical aperture to horizontal free-standing lipid membranes while conrolling membrane voltage and recroding currents using micropatterned Ag/AgCl-electrodes. We demonstrate both wide-field and confocal imaging, as well as time-resolved single photon counting on free-standing membranes spanning sub-picoliter cavities are demonstrated while electrical signals, including single channel activity, are simultaneously acquired. This optically addressable microelectrode cavity array will allow combined electrical-optical studies of membranes and membrane proteins to be performed as a routine experiment.

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Ensslen, T., Behrends, J. C.. 2022-04-18. A chip-based array for high-resolution fluorescence characterization of free-standing horizontal lipid membranes under voltage clamp. https://doi.org/10.1101/2022.04.18.488685

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